Recently, the general trends in designing electronic devices are toward small size, light weightiness and easy portability. Moreover, with the increasing development of electronic industries, the internal circuitries of the electronic devices are gradually modularized. In other words, plural electronic components are integrated into a single electronic module. For example, a power module is one of the widely-used electronic modules. An example of the power module includes but is not limited to a DC-to-DC converter, a DC-to-AC converter or an AC-to-DC converter. After the electronic components (e.g. integrated circuit (IC) chips, capacitors, resistors, inductors, transformers, diodes and transistors) are integrated as a power module, the power module may be installed on a motherboard or a system circuit board.
Nowadays, an embedded package structure is widely adopted because of many advantages such as smaller footprint, lower profile, higher power density and performance, better thermal management, lower electrical noise and mass production.
However, the conventional embedded package still has some drawbacks. For example, thickness of the conventional embedded package is generally more than 350 μm without a passive component. Consequently, it is difficult to reduce the space of the power module. Moreover, a re-distribution layer (RDL) is an extra metal layer formed on the electronic components of the embedded package structure that makes the conducting terminals of the electronic component available in other locations. The conventional embedded package forms the re-distribution layer (RDL) by photolithography process, so that the process of the conventional embedded package may increases cost. In addition, the electrolytic copper plating process easily causes non-uniform thickness of the re-distribution layer of the conventional embedded package.
Therefore, there is a need of providing an improved packaging process in order to eliminate the above drawbacks.